“What about setting up a wiki-style website and let us supply and choose our translations”
It is a fantastic idea. I am a quick hand and I created a Wiki site tonight and it is online now.
The idea behind is Wiki is what Qingsi suggested: to supply and choose a better translation to the misspelled words or grammer mistakes.
The Wiki site also serves as a place for you to report other significant typos in this city. I am not very sure what we can do with the result yet, but I guess the media or the government will notice it one day and push for the correction.
Before you get started, do follow all the rules of the Wiki world. Thanks.